- 2007–2009 Factory-verified
Also described as Alarm, vehicle speed, 120 kilometers per hourVehicle speed alarm, 120 km/h (overspeed warning)
Also documented for BuickCadillacChevroletHummerOldsmobilePontiacSaturn
Documented applications
- 2003–2009 Factory-verified
- 2000, 2001 Factory-verified
- 1999–2001, 2004, 2005 Factory-verified
The list prints "120 KPH"; the 2004 and 2005 lists read "120 K/h".
- 1998–2002 Factory-verified
- 2003, 2006–2010 Factory-verified
the 2015–2016 Upfitter manuals still print the code with do not use after 2010 on new major programs, use the country code or VCS family code instead, so later years are not claimed
- 1998–2000 Factory-verified
- 1999–2007 Factory-verified
- 2009 Factory-verified
- 2001–2007 Factory-verified
- 2007–2009 Factory-verified
- 2000–2004 Factory-verified
- 1998–1999 Factory-verified
- 1998–1999 Factory-verified
- 2000–2002, 2004–2006 Factory-verified
the 2000 list words it as an overspeed warning device required for Saudi Arabia, the Gulf States and Kuwait
- 2007–2009 Factory-verified
This page aggregates every documented appearance of UD4 in the GMC reference. Confidence and citations are shown per application — the same code can be better documented in one year than another.